Previously, pointer casting was used, but this resulted in strict-aliasing warnings: IPAddress.h: In member function ‘IPAddress::operator uint32_t() const’: IPAddress.h:46:61: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] operator uint32_t() const { return *((uint32_t*)_address); }; ^ IPAddress.h: In member function ‘bool IPAddress::operator==(const IPAddress&) const’: IPAddress.h:47:81: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] bool operator==(const IPAddress& addr) const { return (*((uint32_t*)_address)) == (*((uint32_t*)addr._address)); }; ^ IPAddress.h:47:114: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] bool operator==(const IPAddress& addr) const { return (*((uint32_t*)_address)) == (*((uint32_t*)addr._address)); }; Converting between unrelated types like this is commonly done using a union, which do not break the strict-aliasing rules. Using that union, inside IPAddress there is now an attribute _address.bytes for the raw byte arra, or _address.dword for the uint32_t version. Since we now have easy access to the uint32_t version, this also removes two memcpy invocations that can just become assignments. This patch does not change the generated code in any way, the compiler already optimized away the memcpy calls and the previous casts mean exactly the same. This is a different implementation of a part of #1399 and it helps toward fixing #1728.
Arduino
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Arduino is an open-source physical computing platform based on a simple i/o board and a development environment that implements the Processing/Wiring language. Arduino can be used to develop stand-alone interactive objects or can be connected to software on your computer (e.g. Flash, Processing, MaxMSP). The boards can be assembled by hand or purchased preassembled; the open-source IDE can be downloaded for free.
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For more information, see the website at: http://www.arduino.cc/ or the forums at: http://arduino.cc/forum/
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To report a bug in the software or to request a simple enhancement go to: http://github.com/arduino/Arduino/issues
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More complex requests and technical discussion should go on the Arduino Developers mailing list: https://groups.google.com/a/arduino.cc/forum/#!forum/developers
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If you're interested in modifying or extending the Arduino software, we strongly suggest discussing your ideas on the Developers mailing list before starting to work on them. That way you can coordinate with the Arduino Team and others, giving your work a higher chance of being integrated into the official release https://groups.google.com/a/arduino.cc/forum/#!forum/developers
Installation
Detailed instructions are in reference/Guide_Windows.html and reference/Guide_MacOSX.html. For Linux, see the Arduino playground: http://www.arduino.cc/playground/Learning/Linux
Credits
Arduino is an open source project, supported by many.
The Arduino team is composed of Massimo Banzi, David Cuartielles, Tom Igoe, Gianluca Martino, Daniela Antonietti, and David A. Mellis.
Arduino uses the GNU avr-gcc toolchain, avrdude, avr-libc, and code from Processing and Wiring.
Icon and about image designed by ToDo: http://www.todo.to.it/